Bump langchain in /ai/generative-ai-service/patient-letter-extraction

Bumps [langchain](https://github.com/langchain-ai/langchain) from 0.1.10 to 0.2.5.
- [Release notes](https://github.com/langchain-ai/langchain/releases)
- [Commits](langchain-ai/langchain@langchain-groq==0.1.10...langchain==0.2.5)

---
updated-dependencies:
- dependency-name: langchain
  dependency-version: 0.2.5
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

ai/generative-ai-service/patient-letter-extraction/requirements.txt

@@ -1,6 +1,6 @@
 pandas==2.1.4
 jsonschema==4.19.2
-langchain==0.1.10
+langchain==0.2.5
 streamlit==1.30.0
 langchain-community==0.0.32
 pdf2image==1.16.3